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Building a Personal Clean Room?
eagleyezx asks: "I have a rather large basement with nothing currently sitting in it (I moved all my crud to my garage). Since I am really into space and satellites, I have a satellite all designed. It's kinda based on one of the Amsat designs, but all it really does it beep, just like Sputnik. However, I would need a sterile clean room to build one that would function properly and not go beserk in orbit. I know everyone out there has thought about this at least once? Has anyone ever built a room like this? Any suggestions on equipment?" If you had the drive to do something like this, what would you need to do to be able to build a workshop that would even come close to "clean room" standards. Has anyone ever built an airlock on the cheap?
Is that like military and intelligence?
seriously though I really don't think it is possible. Though to start with you would need:
1) A large air conditioner
2) Several filters of variing ratings (start with normal airconditioner filters then move to heppa filters then ionization filters and liquid filters
3) A way of sealing the room completely maybe like the thermal sprays they put on buildings (it is air tight and non brathable IIRC)
4) a decent multistage airlock
5) Appropriate dress
Seriously the trick to a clean rom is all in keeping things out. so a good start is to us ethe previously filtered air to create an over pressure area inside teh clean room. This if there are any leaks they would be to the outside not the inside. Good luck
Bad Panda! No Bamboo for you! In matters of importance ACs will not be responded to. Want to say something critical,OK
Satellites won't go bezerk in orbit if they're not built in a clean room. Especially a beeper like the one you envision. You've got your horse before your cart too. When you build this thing, how are you going to get it into orbit? For that matter, when you build this thing, how are you going to get it out of your basement? The satellite and mounting hardware and mating ring to attach to the rocket are not going to fit up your stairs!
Anyway, just in case you are the next Werner von Braun, I wouldn't like to be remembered by history as "that guy who treated a genius rudely" I will answer your question. Remember the train conductor who was wrongly blamed for making Edison deaf when he actually saved his life? You know what I'm talking about...
Take a look at pages written by those who paint their cars at home in their garages. To get those nice smooth paint jobs there can't be any dust around.
Get your stinking paws off me you damn dirty ape
I've actually done clean-room-level work (doing whisker rework on bare-die chips and messing around with hard-drives) without a cleanroom and actually never had any problems. Granted I was in an office environment with decent filters and I kept the door closed and tried not to stir things up too much while I was working - ymmv! :)
However, I have to ask, why do you need a clean-room? Everything's going to be solid-state (and epoxy or ceramic packaged) and/or large enough mechanically (e.g. solar-array deployment) that it shouldn't matter. Unless you're conducting experiments with MEMs or something...? Whatever.
Besides, if you just leave provide enough gaps in the seams to let the air out as soon as that sucker hits vacuum - whoosh! - it'll be really clean!
(Er, um, this whole article isn't a clever troll is it...?)
Clean rooms are rated as class 1, class 10, class 100, class 1000 and class 10,000. The numbers are the maximum count of 0.5 micron sized particles permitted in a cubic foot of air. The old federal standard for clean rooms is FED STD 209E, recently replaced by the international standard ISO 14 644. I'm guessing the ISO standard costs bucks and the FED standard is probably free so pick and choose. A class 1000 clean room would not be that hard to build and maintain. Clean, painted surfaces all around, some sort of air filtration system with positive pressure, no textiles, pencils, powdered gloves allowed. You'd have to wear clean room smocks, booties and bonnet. The room would have to be vacuumed daily (with a vacuum exhausting to the outside) and the particulate count verified daily. An air shower and sticky mat at the entrance would be a good thing. Now that's just for a class 1000 clean room. Imagine what it takes for a class 1 clean room.
"Eve of Destruction", it's not just for old hippies anymore...
For starters you'll need a really big fan, just to driver the air-flow through the filters and your room. The trick is to have an over-pressure and a good flow. The over-pressure prevents stuff from getting in, and the flow removes stuff that already are in (you'll probably carry in some dust, etc.).
What parts are you going to assemble in a clean room. I'd rather suggest a clean-box (i.e. a box with a good clean air-flow and gloves epoxied to a couple of entry points to allow you to work in there. Simply put your working project (in transport protection) in there, your tools (do *not* forget anything), then let the air flow through. When the air has been completely exchanged a few times you can get your working project out of the transport protection and get working on it. When you are done, simply wrap it into something air-tight again and then remove it from your working box.
Such a solution would be easier to work with and have a higher wife-acceptance-factor. Of course, it requires that whatever your doing fits into the box.
We used a cleanroom like the following on the ATLAS Muon Detector project at the University of Washington. It was pretty low-tech, but it did a good job at keeping things clean. I don't remember the rating of the clean room, but all we had to do was wear a clean suit over our street clothes, latex gloves, shoes over our street shoes, and a cap. The clean suit, show covers, and caps were made from a special material. You can buy them in bulk from companies like 3M.
The room was constructed like any other room. The "airlock" was more like a changing room / entry way. There was a coat hook where we hung our clean suits, and a sticky floor that would get the majority of the grime off of our shoes. When the sticky floor got all dirty, we would peel off a layer. Inside the clean room and in the entry way, the walls were made of white plastic that didn't get electricaly charged and so wouldn'a allow lint to stick to it. The sections of wall were joined by aluminum strips about three inches wide.
The roof had several holes with air filters in them. One end of the room had a "wall fan" - the entire wall was a fan behind some air filters that would suck the air out of the room. So the air flow would come down through the roof filters and out the wall. The filters were better than the variety you might have in your house, but weren't super expensive. The floor was made of linoleum - a light color. Light colors help expose dirt and lint and such.
We mopped the floor every week as it would slowly accumulate dirt and gunk. The actual "clean room" was everything above our waist as the air below that couldn't be trusted as it wasn't being constantly filtered. As long as the air was flowing, we were pretty clean. We also made sure to stay out of the airflow of what we were working on. This means we couldn't lean over the parts and machines we were building.
We assembled a table that had a stainless steel surface. It was easy to keep clean with lint-free wipes and alcohol, but rarely needed it unless we spilled something.
We also made sure the parts were meticulously cleaned before being admitted into the clean room. Once in the clean room, we would clean them again.
Our clean room didn't have a machine that would count the number of impurities in the air, but I once worked in one that did. However, that clean room was much more strict and had the fans under the floor. We had to wear full body suits and face masks for that. That was the clean room for the Sudbury Neutrino project. They assembled the nickel tube detectors in that one.
The radical sect of Islam would either see you dead or "reverted" to Islam.
I worked for the high energy physics department in college. My team built hardware for the CLEO detector at Cornell and D0 detector at Fermi. Part of the project was testing some mircochips which contained ADCs for monitoring voltages. These chips had not been packaged or enclosed in anything. They had just been wire bonded to long strips with fine wires. Any bit of material falling on these chips could ruin them...so, we worked in the clean room.
Our clean room was really just a large area enclosed in heavy transparent plastic of a heavy grade with an air filer and blower on top. Like a tent. The plasctic hung from a steel frame and was an inch or so off the ground. The system worked by there being a positive pressure in the clean room. No dust could get in through the openings. Its too hard to build an airtight room...much easier just to use positive pressure in the clean zone. The system we used was a kit. I'm not sure how much it cost...the univ took care of that. I helped with some of the assembly, mostly it was done by the campus plant guys, but we hung the plastic and installed the filters ourselves.
There were 4 blowers on top of the room with really fancy filters. One of them had an air conditioner attached to its intake to keep us from getting to warm in our box. It was fun.
I think you could duplicate somthing like this fairly easily. A lot of it depends on how clean you want the room...they come in different grades.
Filters and positive pressure only work to a certain grade. I don't have numbers, been too long.